The training ground incident between Oscar and Diego Costa was described as "two wolves bumping chests" by Chelsea interim manager Guus Hiddink.

The pair faced up to each other after a challenge from midfielder Oscar into the back of striker Costa on Thursday.

"Oscar apologised in front of the group and they all started laughing, jokes were made," said Hiddink.

The Premier League champions face League One side Scunthorpe in the third round of the FA Cup on Sunday.

Oscar laughed off the incident on Twitter

Chelsea have struggled in the league this season, lying in 14th place, and sacked manager Jose Mourinho last month after he won the title for the club in the previous season.

The Telegraph reported the two players had to be separated following an "outrageous" challenge from Brazilian Oscar at Chelsea's Cobham training ground.

But Hiddink - who won the FA Cup in his previous spell in charge of the Blues in 2009 - played down the incident.

"It's a pity that our photographer had a day off or he could have shot beautiful pictures from the two", he said.

"They were jesting a bit after a charge from behind from the smaller of the two, Oscar. Costa took a charge from behind and it was overdone, especially when you know Oscar is not the biggest tackler of the team.

"They stumbled over the ground, stood up, as a normal reaction, they jested a bit, but we came in between them to say that there was no need to hit each other.

"Those things happen when you're close on the edge. Oscar apologised for over-reacting, then they looked at each other and started laughing. It was a normal battle."